Aberrant crypt foci and AgNORs as putative biomarkers to evaluate the chemopreventive efficacy of pronyl-lysine in rat colon carcinogenesis.

Chemoprevention opens new perspectives in the prevention of cancer and other degenerative diseases. Use of target-organ biological models at the histological and genetic levels can markedly facilitate the identification of potential chemopreventive agents. Our aim was to study the chemopreventive efficacy of pronyl-lysine, a key antioxidant present in bread crust by evaluating, the total number of aberrant crypt foci (ACF), their distributions, dysplastic ACF, colonic tumor incidence and the expression of cell proliferation biomarker such as the argyrophilic nucleolar organizing region-associated proteins (AgNORs) in 1,2-dimethylhydrazine (DMH) induced colon cancer in rats. Male Wistar rats were randomized into seven groups, group 1 were control rats, group 2 received pronyl-lysine (2 mg/kg body weight p.o. everyday), rats in groups 3-7 were administered DMH (20 mg/kg body weight) in the groin for 15 weeks. In addition, group 4 (pre-initiation), 5 (initiation), 6 (post-initiation), and 7 (entire period) received pronyl-lysine (2 mg/kg body weight p.o) everyday. At the end of 34 weeks, pronyl-lysine supplementation showed markedly reduced tumor incidence, ACF development and also lowered number of AgNORs. Overall, these findings confirm that pronyl-lysine has a positive beneficial effect against chemically induced colonic preneoplastic progression in rats.